I Had A Torn Meniscus Surgery. On The Fourth Day

I had a torn meniscus surgery. On the fourth day per docs orders, removed dressing to shower. To my surprise, entire knee cap was extremely red and I had what I thought was a bruise on top of my knee. Two days later the "bruise" festered into a blister the size of a fifty cent price. The physical therapist never seen any thing like it, nor did the docs PA ( doc was on vacation). Five weeks later the doc seen and said it was normal, dried blood. The blister dried up and scab over. I now have a a brown sop pot that the doc said will take a year to go away